Lionel Messi's substitution late in Thursday's 4-2 Copa del Rey quarter-final second leg win at Malaga was just a "precaution" and the Barcelona talisman should be fine to start Sunday's La Liga game against Osasuna at the Camp Nou.

Soon after setting up a semi-final against Real Madrid by heading Dani Alves' cross past Malaga keeper Carlos Kameni, Messi, 25, signalled to the Barca bench that he wished to come off and surprisingly left the pitch to whistles from the home fans.

Stand-in boss Jordi Roura - in charge as Tito Vilanova was in New York continuing his recovery from December's parotid gland operation - said after the game that the Argentina international had felt a problem in his thigh, but there was no cause for further concern.

"Messi told us that he felt something in his adductor muscle," Roura said. "We brought him off the pitch as a precaution. His right leg was giving him problems. It is nothing serious."

Messi was joined on the scoresheet by team-mates Pedro Rodriguez, Gerard Pique and Andres Iniesta, along with Malaga's Joaquin and Roque Santa Cruz, in a high-quality game played at a frantic pace.

The result saw Barca through 6-4 over the two legs, leading Roura to praise the show his players had put on.

"Once again, these players proved what they are made of," he said. "They gave a footballing lesson, and they have given quite a few. Frankly, the whole team played well."

The assistant coach declined to speak about next Wednesday's Copa semi-final first leg at the Bernabeu, saying that the game could wait until after Barca had protected their La Liga lead this weekend.

"We have a very important game against Osasuna on Sunday and I prefer to not talk about Real Madrid," he said.